mTOR/miR-145-regulated exosomal GOLM1 promotes hepatocellular carcinoma through augmented GSK-3β/MMPs

Xiaochen Gai1, Bufu Tang2, Fangming Liu1

  • 1State Key Laboratory of Medical Molecular Biology, Department of Physiology, Institute of Basic Medical Sciences and School of Basic Medicine, Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100005, China.

Insights

The mammalian target of rapamycin (mTOR) pathway negatively regulates microRNA-145 (miR-145), which targets Golgi membrane protein 1 (GOLM1). This mTOR/miR-145/GOLM1 pathway is a potential therapeutic target for hepatocellular carcinoma (HCC).

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Golgi membrane protein 1 (GOLM1), also known as GP73, is a validated serum marker for hepatocellular carcinoma (HCC).
  • Previous research established that the mammalian target of rapamycin (mTOR) pathway promotes HCC tumorigenesis by upregulating GOLM1 expression.

Purpose of the Study:

  • To elucidate the regulatory relationship between mTOR, microRNA-145 (miR-145), and GOLM1 in HCC.
  • To investigate the functional roles of GOLM1 and miR-145 in HCC progression and metastasis.
  • To evaluate the potential of targeting the mTOR/miR-145/GOLM1 pathway for HCC treatment.

Main Methods:

  • Investigated the effect of mTOR on miR-145 expression using molecular assays.
  • Validated miR-145 targeting of GOLM1 at the coding sequence level.
  • Analyzed the correlation between GOLM1 and miR-145 expression in human HCC tissues.
  • Assessed the functional impact of GOLM1-enriched exosomes and miR-145 on HCC cell proliferation and migration.
  • Examined the involvement of the glycogen synthase kinase-3β/matrix metalloproteinases (GSK-3β/MMPs) signaling axis.

Main Results:

  • Demonstrated that mTOR acts as a negative regulator of miR-145 expression.
  • Confirmed that miR-145 directly inhibits GOLM1 expression by targeting its coding sequence.
  • Observed an inverse correlation between GOLM1 and miR-145 levels in human HCC tissues.
  • Showed that GOLM1-enriched exosomes promote HCC cell proliferation and migration via the GSK-3β/MMPs pathway.
  • Confirmed that miR-145 suppresses HCC tumorigenesis and metastasis.

Conclusions:

  • The mTOR/miR-145/GOLM1 signaling pathway plays a critical role in HCC development and progression.
  • miR-145 acts as a tumor suppressor by inhibiting GOLM1 and downstream signaling.
  • Targeting the mTOR/miR-145/GOLM1 pathway represents a promising therapeutic strategy for hepatocellular carcinoma.

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